ABB achieves breakthrough with world’s most powerful HVDC transformer

ABB writes next chapter in electrical history as transformers and key equipment for world’s first 1,100 kilovolt (kV) project in China pass stringent tests. 

ABB has set another pioneering innovation record with the successful testing of the low and high voltage units of the world’s most powerful ultrahigh-voltage direct current (UHVDC) transformer. The +/-1,100 kV (1.1 million volts) UHVDC transformer, developed and manufactured in close collaboration with State Grid Corporation of China (SGCC), has successfully passed a series of type tests, paving the way for the implementation of the Changji-Guquan UHVDC link, which will transmit power from the Xinjiang region in the Northwest, to Anhui province in eastern China.

Changji-Guquan, the world’s first +/-1,100 kV UHVDC link will set a new world record in terms of voltage level, transmission capacity and distance. It will be capable of transporting 12,000 megawatts of electricity - the equivalent of 12 large power plants and 50 percent more than the +/- 800 kV UHVDC links currently in operation. Transmission distance will be extended from around 2,000 kilometers (km) to over 3,000 km, enabling the integration and transmission of remote renewables on a much larger scale.

When fully operational this UHVDC link will be able to feed eight 500 kV and two 1,000 kV AC lines – delivering power equivalent to twice the average annual power consumption of Switzerland. ABB’s latest breakthrough also makes it possible to connect +/-1,100 kV DC with 750 kV UHVAC links for the first time. In addition to the transformer, ABB has also developed and successfully tested a range of other key +/-1,100 kV components, including converter valves, bushings and DC circuit breakers.

“In addition to transporting more power across longer distances with lower losses, this breakthrough will enable the interconnection of AC and DC grids and support the future linking of regions and countries.” said Claudio Facchin, president of ABB’s Power Grids division. “It reinforces our pioneering technology leadership in HVDC transmission and reaffirms our close collaboration with SGCC, as we enable a stronger, smarter and greener grid”.

“The Changji-Guquan +/-1,100kV project is a major technical step-up making it the world’s highest DC voltage. The transformer is a key element of this link and we are pleased that the first of these landmark transformers have passed critical tests and exceeded expectations. I would like to congratulate the teams from ABB and SGCC on this successful achievement” said Mr. Liu ZeHong, Executive Vice President, SGCC.

China has major consumption centers in the east, while a significant amount of its energy resources are in the west and northwest. The expansive geography and increasing demand have prompted the build-up of ultrahigh voltage links to increase transmission capacity while minimizing losses.

ABB pioneered HVDC technology more than 60 years ago and is the global market leader with over 110 HVDC projects, representing a total installed capacity of more than 120,000 megawatts - around half of the world’s installed base. UHVDC transmission is an advancement of HVDC and represents the biggest capacity and efficiency leap in over two decades. In 2010 ABB supported SGCC with the Xiangjiaba-Shanghai project, the world’s first +/- 800 kV UHVDC link to go into commercial operation.